Filter backwash nozzle

ABSTRACT

A nozzle is disclosed for use within a filter for inputting a jetting stream into the filter media to clean the filter media. The nozzle comprises an inlet for communication with a jetting stream source, and a plurality of plates stacked parallel and abutting one another. The plurality of plates comprises at least a top plate and a bottom plate, one of the plates having an aperture through the center thereof for receiving the jetting stream, wherein between adjacent plates at least one space is provided extending from the outside edge of the plates to the interior of plates and in fluid communication with the aperture for channeling the jetting stream radially outward from and substantially parallel with the longitudinal plane of the plate.

CROSS-REFERENCE

This application is a continuation of U.S. patent application Ser. No.14/718,549 filed on May 21, 2015, which claims the benefit of priorityfrom Canadian Patent Application no. 2,891,856 filed on May 19, 2015(now issued on Nov. 8, 2016 as Canadian Patent no. 2,891,856).

FIELD OF THE INVENTION

The present invention relates generally to the field of liquidfiltration using non-fixed filter media, and more specifically to anozzle for use in a method and system for removing filtered contaminantsfrom non-fixed filter media filter beds, such as granular filter mediafilter beds, during periodic cleaning cycles.

BACKGROUND

Various types of methods and systems have been used to removeaccumulated contaminants from a bed of granular filter media. Themethods utilized to date generally have the following common processingsteps: 1) providing an agitation means to break-up agglomerations offilter media and contaminants typically formed during the filtrationprocess, 2) flowing a carrier medium through the agitated granules tomobilize the contaminants away from the filter media, 3) retaining thefilter media while allowing contaminants to flow out, and 4) returningthe cleaned filter media back to its normal state. These four steps canbe condensed to the following: 1) agitation, 2) washing, 3) separating,and 4) reforming.

With regard to common step 1, various means are disclosed to agitate thefilter media such as rotary blades and high-velocity liquid jets (SeeU.S. Pat. Nos. 2,521,396 and 3,992,291/3,953,333). However, both ofthese methods create at least two significant problems. First, rotaryblade systems often have mechanical seals that require frequentmaintenance. Second, the high-velocity liquid jets produce large volumesof dirty backwash water that must be stored and recycled through theprocess. What is needed in the art is an agitating means that does notrequire rotating internal baffles or impellers and reduces or minimizesliquid usage.

With regard to common step 2, the carrier medium used to flush thefilter media is most commonly the clean filtrate fluid. In many systems,large volume storage of clean filtrate is required to provide surgecapacity when the backwash cycle draws a high-volume rate to flush themedia during this step. Some methods utilize the high-volume water jetsto both agitate and back flush, which is a combination of common steps 1and 2. However, such systems still generate large volumes of backwashliquid that must be stored and recycled back through the process. Also,it would be ideal to utilize contaminated process fluid for backwashinginstead of clean filtrate. This would avoid having to have cleanfiltrate storage vessels and pumps specifically for periodic backwashingcycles.

With regard to common step 3, separation of the contaminants from thefilter media is typically done by flowing the slurry in a continuousflow path over a cleaning element, located external to the filterhousing, where interspersed larger particulates are removed from theslurry, and returning the withdrawn filter material back to the filterhousing (See U.S. Pat. Nos. 3,992,291 and 3,953,333). This method addssignificant cost and size to the filter since it requires variousexternal conduits, vessels, valves and equipment. U.S. Pat. No.4,787,987 discloses an in-situ method of separating the contaminantsfrom the filter media by a screen, of size slightly smaller than thefilter media size, contained within the vessel below the filter media.That method agitates and slurrifies the media and contaminants by actionof a high-volume liquid pump. During this agitation step, make-up liquidis added to the vessel at substantially the same rate that theconcentrated contaminated liquid is removed through the screen meanswhile the filter media is retained within the filter housing.

A more recent development involves a method of in-situ cleaning ofagglomerated contaminants from granular filter media. This methodcombines a low rate of contaminated liquid with a gas, such as air ornatural gas, to create a jetting stream. This jetting stream isdispersed into the filter media through one or more radial nozzlesdisposed within the filter media. The gas exits the radial nozzles as abubble dispersion within the liquid. As the jetting stream rises upthrough the filter media, it expands the bed to break large contaminantagglomerations and fluidizes the individual filter media granules todislodge and mobilize smaller contaminant agglomerations within theinterstitial spaces of the filter media. The radial nozzles consist oftop and bottom circular plates of a diameter D and are spaced apart by agap that is smaller than the smallest sized filter media granule. Thetwo plates are separated by a spacer washer and bolted together whichcreates dead areas around the circumference of the jet where the boltsblock the flow. Further, the two plates limit the amount of flow.

A need exists for an improved nozzle that avoids the need for a spacerwasher while allowing for consistent flow of a jetting stream generallyradially outward from the nozzle and consistent flow rates and/orpressures across the height of the nozzle.

SUMMARY OF THE INVENTION

In one embodiment, the present invention provides for a nozzle for usewithin a filter for inputting a jetting stream into the filter media,the nozzle comprising:

an inlet for communication with a jetting stream source;

a plurality of plates stacked parallel and abutting one another, theplurality of plates comprising at least a top plate and a bottom plate,one of the plates having an aperture through the center thereof forreceiving the jetting stream, wherein between adjacent plates at leastone space is provided extending from the outside edge of the plates tothe interior of plates and in fluid communication with the aperture forchanneling the jetting stream radially outward from and substantiallyparallel with the longitudinal plane of the plate.

In a further embodiment of the nozzle or nozzles outlined herein, theplurality of plates further comprising one or more intermediate plateshave a top side facing towards the top plate and a bottom side facingtowards the bottom plate and each intermediate plate comprises anaperture through the center thereof for receiving the jetting stream,the apertures of the intermediate plates and the top plate being influid communication.

In a further embodiment of the nozzle or nozzles outlined herein, thespace is provided by a channel in the one of the plates and the side ofthe adjacent parallel stacked and abutting plate.

In a further embodiment of the nozzle or nozzles outlined herein, thespace is provided by a channel on the top side of each plate and thebottom side of the adjacent parallel stacked and abutting plate.

In a further embodiment of the nozzle or nozzles outlined herein, thechannel in the plate further defines a ridge which abuts the bottom sideof the adjacent parallel stacked and abutting plate.

In a further embodiment of the nozzle or nozzles outlined herein, thereare a plurality of spaces between each adjacent plate.

In a further embodiment of the nozzle or nozzles outlined herein, theridge has an impellor shape for guiding the jetting stream radiallyoutward from the aperture.

In a further embodiment of the nozzle or nozzles outlined herein, theridge has a height of between 2 and 30 mm.

In a further embodiment of the nozzle or nozzles outlined herein, atotal number of plates is from 2 to 9.

In a further embodiment of the nozzle or nozzles outlined herein, thetotal number of plates is from 3 to 7.

In a further embodiment of the nozzle or nozzles outlined herein, thetotal number of plates is 5.

In a further embodiment of the nozzle or nozzles outlined herein, thetotal number of plates is 6.

In a further embodiment of the nozzle or nozzles outlined herein, theinterior diameter of each aperture in the center of the intermediateplates and the top plate is successively reduced for plates positionedtowards the bottom plate.

In a further embodiment of the nozzle or nozzles outlined herein, thereduction in interior diameter of the aperture in the center of platesis sufficient to substantially counteract the reduction in flow volumeor flow rate of the jetting stream as it approaches the bottom plate.

In a further embodiment of the nozzle or nozzles outlined herein, thegap defined by the distance between stacked plates is successivelyreduced for plates positioned towards the bottom plate.

In a further embodiment of the nozzle or nozzles outlined herein, thereduction in the gap is sufficient to substantially counteract thereduction in flow volume or flow rate of the jetting stream as itapproaches the bottom plate.

In a further embodiment of the nozzle or nozzles outlined herein, theplates comprise an aligning notch in their outer periphery enablingvisual or physical alignment of the stacked rings prior to connection ofthe plates.

In a further embodiment of the nozzle or nozzles outlined herein, theplates of the nozzle are welded together, preferably welded at aposition of the outer periphery thereof.

In a further embodiment of the nozzle or nozzles outlined herein, anouter diameter of each the plates of the nozzle is substantially equal.

In a further embodiment of the nozzle or nozzles outlined herein, anouter diameter of each of the plates of the nozzle is substantiallyvaried.

In a still further embodiment, the present invention provides for anozzle for use within a filter for inputting a jetting stream into thefilter media, the nozzle comprising:

an inlet for communication with a jetting stream source;

a plurality of plates stacked parallel and abutting one another, theplurality of plates comprising at least a top plate, one or moreintermediate plates and a bottom plate, the top plate and theintermediate plates having an aperture through the center thereof forreceiving the jetting stream, wherein between adjacent plates aplurality of spaces are provided extending from the outside edge of theplates to the interior of the plates and in fluid communication with theaperture in the center of the plates for channeling the jetting streamradially outward from and substantially parallel with the longitudinalplane of the plates;

wherein the plurality of spaces is provided by a plurality of channelsin the one of each of the plates and the side of the adjacent parallelstacked and abutting plate and wherein each channel is defined by aflanking ridge that abuts the adjacent parallel stacked and abuttingplate, each ridge having an impellor shape for guiding the jettingstream radially outward from the aperture; and

wherein the interior diameter of each aperture in the center of theintermediate plates and the top plate is successively reduced for platespositioned towards the bottom plate and/or the gap defined by thedistance between stacked plates is reduced successively for platespositioned towards the bottom plate.

In a further embodiment of the nozzle or nozzles outlined herein, thenozzle includes between 3 and 9 plates, between 4 and 7 plates, 5 platesor 6 plates.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a vertical sectional view of an example of a non-fixed mediahousing, showing internal components including an example of a backwashnozzle encompassed by the present invention that may be used forinputting a jetting stream for backwash cleaning of a filter media;

FIG. 2A is an exploded view of one example of a backwash nozzle forinputting a jetting stream for backwash cleaning of a filter media;

FIGS. 2B and 2C are assembled isometric views of one example of abackwash nozzle for inputting a jetting stream for backwash cleaning ofa filter media, wherein FIG. 2C is an enlarged version of FIG. 2B;

FIGS. 2D to 2F are exploded views of some examples of a backwash nozzlefor inputting a jetting stream for backwash cleaning of a filter media,according to some embodiments of this disclosure.

FIGS. 3A, B and C are top, side and isometric views, respectively, of anexample of a top plate of one example of a backwash nozzle for inputtinga jetting stream for backwash cleaning of a filter media;

FIGS. 4A, B and C are top, side and isometric views, respectively, of anexample of an inner plate of one example of a backwash nozzle forinputting a jetting stream for backwash cleaning of a filter media;

FIGS. 5A, B and C are top, side and isometric views, respectively, ofanother example of another inner plate of one example of a backwashnozzle for inputting a jetting stream for backwash cleaning of a filtermedia;

FIGS. 6A, B and C are top, side and isometric views, respectively, ofanother example of another inner plate of one example of a backwashnozzle for inputting a jetting stream for backwash cleaning of a filtermedia;

FIGS. 7A, B and C are top, side and isometric views, respectively, of anexample of a bottom plate of one example of a backwash nozzle forinputting a jetting stream for backwash cleaning of a filter media;

FIG. 8 is horizontal sectional view across the filter housing diameter,showing an example of a possible position of the jetting nozzles in a45° angle between a filtrate outlet sieve manifold;

FIG. 9 is a three-dimensional view of the FIG. 8 embodiment as viewedfrom the underside of the filter housing vessel;

FIG. 10 is a top cross-sectional view similar to that shown in FIG. 8but with the radial nozzles located just below and aligned with theoutlet sieve manifold members showing an alternate location of theradial nozzles;

FIG. 11 shows an alternate embodiment wherein a plurality of filterhousings, each incorporating internal components for carrying out abackwash cleaning method, the plurality of filter housings incorporatedinto one horizontal filter housing separated into individualcompartments by internal baffles;

FIG. 12 is a graph plotting jet pressure drop versus water flow rate,for jets having 5 plates, 6 plates, and 7 plates respectively;

FIG. 13 is a graph plotting jet agitation radius in cm versus water flowrate (gpm) for jet nozzles having 5 plates, 6 plates, and 7 platesrespectively;

FIG. 14 is a graph plotting pressure drop across jet nozzle versus waterflow rate for applications using various flow rates of air; and

FIG. 15 is a graph plotting jet agitation radius versus water flow ratefor a nozzle having 6 plates, with various flow rates of air, with thelargest flow rate of air having the largest jet agitation radius.

DETAILED DESCRIPTION

Described herein are methods, systems, apparatuses, techniques andembodiments suitable for providing a nozzle for use in cleaning filtermedia, optionally in a backwash cleaning method and optionally in afilter comprising non-fixed filter media. It will be appreciated thatthe methods, systems, apparatuses, techniques and embodiments describedherein are for illustrative purposes intended for those skilled in theart and are not meant to be limiting in any way. All reference todimensions, capacities, embodiments or examples throughout thisdisclosure, including the Figures, should be considered a reference toan illustrative and non-limiting embodiment or an illustrative andnon-limiting example.

Referring to FIG. 1, an example of a typical filter vessel 10 isillustrated that may employ a nozzle or nozzles in accordance withvarious aspects of the present invention. The filter vessel 10 houses abed 12 of granular filter medium. The illustrative filter housing is apressure-rated vessel having a 2:1 ellipsoidal upper and lower heads.Other filter vessel shapes and designs may be used and will not affectthe principle operation of the invention. The granular filter media 12may be any of a number of materials chosen based upon thecharacteristics of the liquid to be filtered and the properties of thecontaminants. For filtration of water containing suspended oil dropletsand solids contaminants, a number of different granulated media may beused, such as for example, granulated black walnut shells, ceramic,sand, and/or multimedia. A space 14 exists above the filter bed 12 toprovide room for the bed to expand during the cleaning cycle. It will beappreciated that any suitable filter housing, granular filter mediaand/or space dimension may be utilized.

The filter vessel 10 typically also includes inlet distributors 20 forthe introduction of contaminated liquid from an exterior conduit anddispersing the liquid substantially uniformly across the cross-sectionof the filter vessel. A backwash outlet header 22 may also be installedin the top of the filter vessel for receiving flow of jetting stream andliberated contaminants during a cleaning cycle, for example a backwashcycle. The outlet header may also contain a mechanical sieve means 23,shown here as slotted pipe or wedge-wire where the open slots are of adiameter less than the smallest media granule size to prevent anymobilized filter media from escaping the vessel during the backwashcycle. Although this figure shows separate process fluid inlet andbackwash outlet devices, many inlet distributor designs combine bothprocess fluid distribution and backwash extraction. The description ofthe inlet is illustrative of one embodiment and other feed inlets may beutilized depending on the characteristics of the liquid to be filteredand the contaminants contained therein.

FIG. 1 also shows an example of an outlet header 30 to which may beattached a mechanical sieve 33, shown here as slotted pipe orwedge-wire. After passing through the filter bed, the cleaned filtrateexits the filter vessel through the openings in the sieve 33. Thediameter of the sieve openings is typically smaller than the smallestfilter media granule diameter so that the media is retained inside thevessel during operation.

FIG. 1 shows a plurality of radial nozzles 40 having outlets just belowthe bottom tangent of the mechanical sieves 33. It will be appreciatedby those skilled in the art that the size and shape of the outlet sieves33 and the number of radial nozzles employed will be dependent on thediameter of the filter housing, the volume of backwash desired, thedepth, diameter and/or volume of non-fixed media to be cleaned, etc.

An example of the nozzle 40 shown in FIG. 1 is shown in more detail withreference to FIGS. 2 to 7. The nozzle 40 is comprised of a plurality ofplates, generally two or more, and in various embodiments two to nineplates and in further embodiments between four and seven plates, theplates arranged parallel and adjacent each other. It will therefore beappreciated that the nozzle 40 shown with reference to FIGS. 2 to 7which comprises five plates is merely illustrative of one embodiment ofa nozzle according to the present invention and it is not intended to belimited to the number of plates.

The nozzle 40 is comprised of at least a top plate 100 and a bottomplate 108. In the embodiment shown in FIGS. 2 to 7 the nozzle includesfurther intermediate plates. Each plate comprises opposite flat surfaces101 and 103. The cleaning jetting flows through the center aperture 120in the top plate 100 and the center aperture 114, 116 and 118 in each ofthe intermediate plates 102, 104 and 106, respectively, and radiallyoutward through channels formed in each of the intermediate plates andthe bottom plate. As shown more clearly, for example in FIGS. 4 to 7,the intermediate plates of the nozzle 40 and the bottom plate include aridge such as that shown as 110, 124, 128 and 132 in FIGS. 4 to 7,respectively. Each of the ridges 110, 124, 128 and 132 extends from aflat surface 101 and defines a channel shown as 112, 122, 126 and 130 inFIGS. 4 to 7, respectively, which together with the adjacent platedefine a space or void through which the jetting stream flows into thefilter media bed during the cleaning cycle.

Each plate of the nozzle 40 is stacked parallel, adjacent and abuttingthe next plate and as such, the space or void has a height defined bythe depth of the channel (or the height of the ridge) in each plate. Theheight of the space, and therefore the height of the ridge, should beless than a minimum diameter of the media to be cleaned in the filter toensure that the media, especially if the media is non-fixed, does notpenetrate into the space in the nozzle during regular operation or flowof the fluid through the filter. Typically, the height of the ridge maybe from 2-30 mm. The plates may include a notch 42 that may be used foraligning the plates for connection therebetween. For example, the platesmay be welded to each other, for example on the outer periphery. Forexample, the plates may be tack welded on the outer periphery where theridges meet the adjacent plate.

In the embodiments shown throughout the Figures, the ridges are shown ashaving an impeller shape for providing both the void or space betweenthe channel and bottom side of the adjacent plate as well as for guidingthe jetting stream radially outward from the nozzle. It will however beappreciated that any number of shapes may be used. The shapes and their% of open area may be used to control velocity and flow, and may bemodified to suit different processes and fluids.

The ridges, for example the impellers, may be offset or staggered to aidor allow in evenly distributing the flow of the jetting stream radiallyoutward from the nozzle. It will be appreciated that there is not flowwhere the ridge prevents flow across the plate outward from the inneraperture. Therefore, offsetting the ridges allows for more even flowradially outward from the inner aperture of the nozzle. Offsetting ofthe ridges may be adjusted as required or desired and if differentshaped ridges are used. As compared to plates which are bolted together,even in a plurality of plates, the bolts/washers are generally in linein each stage (gap) of the nozzle thereby not allowing or at leastreducing flow outward about the entire circumference.

The ridges, including impeller shaped ridges, may be machined into theplates or may be added using any suitable means.

Each of the intermediate plates and as well as the top plate include anaperture at the center of the plate to allow for the jetting stream topass into the nozzle for partial redirection radially outward throughthe spaces or voids defined by the channel of each plate and theunderside of the adjacent plate. The bottom plate does not include anaperture as the jetting stream does not pass the bottom plate but iscompletely redirected radially outwards. To facilitate maintaining aconsistent flow rate radially outwards from the center of the nozzleacross all of the plates of the nozzle, each aperture of each plate maybe successively smaller to account for the reduction in flow rate andflow volume of the jetting stream as the jetting stream is radiallyoutput by each plate. To this end, each aperature has a diameter Diwherein each diameter Di of a successive plate may be smaller than theprevious plate.

The diameters of each plate may be adjusted/modified based on theprocess as desired or required given the application. There is awell-known relationship between velocity (v)/flow rate (Q)/diameter (orcross sectional area): Q=v*A where Q is the flow rate, v is thevelocity, and A is the cross sectional area.

It will be appreciated that more plates allow for more flow therebygenerally increasing the radius of influence, reducing the number ofjets required, making it more economical to ideally achieve beneficialmedia bed lift. This can also reduce blocking potential from the media.Multiple plate design can also allow for more flexibility in flow rates.

Alternatively or in addition to reducing the internal diameter of theaperture in each plate, the gap defined by the distance between adjacentor neighboring plates in the stack may be adjusted to influence flowrate or volume and as a result the radius of influence. In oneembodiment, the gap may be reduced successively for plates positionedtowards the bottom plate to counteract the reduction in flow therebysubstantially equalizing flow rate.

With reference to FIGS. 1, 8 and 9, a typical but non-limiting elevationof the radial nozzle outlet void is shown as being approximately evenwith the bottom tangent of the mechanical sieve pipes 33. In many filtervessels, the bottom vessel head may be filled with a solid material,such as grout or concrete, up to the bottom of the mechanical sievepipes. This solid material acts as a support base for the filter mediagranules during normal filter operations since filter media below themechanical sieve pipes is essentially of no effective use. Normally, theradial nozzle outlet voids are placed near the bottom tangent of thesieves pipes 33 so that filter media near the base of the tank can becontacted by the jetting stream. The placement of nozzles near the baseof the filter media bed also allows the jetting stream to clear theopenings of the sieve slots of possible media or contaminantobstructions. For applications where contact with the media near thebase or jetting of the sieve is not required or desired, the height ofthe outlet voids of the radial nozzles may be elevated above the outletmanifold so that the jetting dispersion can penetrate to the fullextremities of the vessel without interference from the outlet manifoldor sieve screens.

The jetting stream, which may be comprised of a mixture of liquid andgas premixed outside of the filter housing, may be carried to the radialnozzle via a conduit 35. This conduit is shown in the drawing as astraight pipe segment connected to a pipe 90° elbow turning down andconnected to the top circular disc of radial nozzle.

For most filter vessel sizes shown, four radial nozzles placed in theproximate center of each quadrant formed by the cross-shaped outletmanifold and sieve pipes will provide adequate coverage of the jettingstream throughout the filter bed cross-section. The lateral extent towhich the radial nozzles disperse the jetting stream is predominantlyset by the rate of water and gas. Therefore, the balance betweenincreasing the water/gas flow rate to each radial nozzle or increasingthe number of radial nozzles across the vessel cross-section is largelya question of economics. The number of nozzles may be increased asneeded to substantially cover the cross-section of the filter vessel,while the placement of the nozzles is largely dictated bycross-sectional symmetry.

FIGS. 8 and 9 show an optional placement of a plurality of nozzles 40across the vessel cross-section in relation to a vessel/nozzlecenterline radius R. This vessel nozzle radius R will vary with filtermedia type, filter vessel diameter, contaminant loading, and contaminantphysical properties. For this particular scenario, an R value in therange of 25% to 36% of the vessel diameter D will typically provideadequate coverage of the jetting stream for effective media agitationcleaning. Depending on vessel diameter and process: other arrangementsmay be used to generate sufficient coverage. Examples of otherarrangements are outlined with reference to FIGS. 11 and 12.

FIG. 10 shows an optional alternate location of the four nozzles shownas dotted circles 42 rotated 45° from the positions shown in FIG. 8 andFIG. 9 and located just below the mechanical sieve screens 33. Byrotating the radial nozzles 40 in line with the mechanical sieve screensand elevating/lowering them just above/or below the top/or bottomtangent of the circular size screens, the jetting stream will have areduced degree of interference with the sieve screens. These locationsmay, for example, be more desirable for filter applications where thereare space constraints or based on the settling of the contaminants inthe filter media. A benefit of these arrangements can be that“blind-spots” are minimized since the vertical movement of the jettingstream is not impeded by contact with the sieve screen members as mayoccur in other embodiments shown. It will be appreciated that multipleelevations may be used in a single application and that the invention isnot limited to these locations or elevations.

In reference to FIG. 11, an embodiment is presented wherein severalfilter housings, containing the internal members described herein forcarrying out the cleaning method and shown in the previous Figures, areplaced inside a singular horizontal vessel 80 and separated by aplurality of dividing baffles 84. Note that for clarification purposes,the component numbers of the embodiment in the figure are shown for onechamber and it is to be understood that each chamber has substantiallyidentical components. Each filter chamber may contain a process inletnozzle 82 and a process outlet nozzle 81. A plurality of piping conduitsmay connected to these inlet and outlet connections so that the processfluid may flow into each chamber in parallel. In such a filter, a largefluid processing volume is allowed without requiring a large number ofradial nozzles to be installed to ensure adequate jetting coverage asmight be required if the filtration were carried out in a single largefilter vessel. Alternatively, the piping conduits connecting thechambers may be done so that the fluid to be filtered flows through eachchamber in a series manner. Such a flow pattern may be advantageouswhere each chamber contains a different media type that has a uniqueaffinity for a particular fluid contaminant or particle size. In thistype of filter arrangement, the amount of jetting stream required tobreak-up and mobilize the contaminants during the cleaning cycle may bevaried independently to each chamber to optimize the cleaning cycle.

The jetting stream flowing to the radial nozzles inside the filterhousing may be comprised of a pre-mixed stream of a compressed gas andliquid flowing to each nozzle from a common header. Connected to thiscommon header is a source of a pressurized gas and pressurized liquid.Each of these streams may flow into the common distribution headerthrough a control element and metering device such that the filteroperator can adjust the rate of gas and liquid flowing to the nozzles.Typical gas source is natural gas. However, any inert gas would beapplicable. For economic reasons, the liquid source typically used bythe inventors is the incoming contaminated process fluid.

The amount of liquid and gas flowing into the common header may largelybe dependent on the overall size of the filter housing. It has beenobserved that approximately 9 gpm (gallons per minute) of water persquare foot of bed area and 0.7 SCFM (standard cubic feet per minute) ofgas per cubic foot of bed provide adequate performance for cleaningblack walnut shells filtering oil and solids from produced water.Converting these values to a common volumetric unit gives a typicalvalue of 1.7 cubic feet of liquid per square feet of bed area perstandard cubic feet of gas per cubic feet of filter media inside thehousing. This ratio will vary to some extent based on the size of thevessel, the number of radial nozzles used, the size and volume of filtermedia being cleaned, and the physical characteristics of thecontaminants. Therefore, it is understood that part of the operation ofthis type of filter is adjusting the liquid and gas stream rates tooptimize the media cleaning cycle performance while minimizing theamount of contaminated liquid remaining for disposal or recycling.

FIGS. 12 and 13 shows additional illustrative embodiments of non-fixedmedia filter vessels 200 and 202, respectively, with various optionallayouts of the radial nozzles 40 for inputting a jetting stream forcleaning the media, for example in a backwash cleaning cycle. FIGS. 12and 13 simply show various optional positioning of the radial nozzles 40in examples of filter vessels and are for the purpose of illustratingthat a plurality of filter vessels, housings, architectures and/orheaders may be implemented. FIG. 12 shows a vertical non-fixed mediafilter vessel 200 while FIG. 13 shows a horizontal non-fixed mediafilter vessel 202. The radial nozzles 40 may be nozzles such as thosedescribed herein, for example with reference to FIGS. 2-7.

It will be appreciated that that various modifications, amendments,variations, additions or alterations may be made to the apparatuses,systems and methods outlined herein without departing from the spirit orscope of the invention. Such modifications, amendments, variations,additions or alterations are intended to be within the contemplation ofthe invention.

We claim:
 1. A nozzle for use within a filter for inputting a jettingstream into filter media, the nozzle comprising: an inlet forcommunication with a jetting stream source; a first plate and at leastone second plate stacked parallel and in mutual juxtaposal position, thefirst plate having an aperture through the center thereof for receivingthe jetting stream, each of the first and at least one second platehaving opposite flat surfaces perpendicular to a stacking directionthereof, wherein each of the at least one second plate includes at leasta pair of ridges on one of the opposite flat surfaces thereof defining aplurality of channels, each pair of ridges defining a respective channelbetween them and between said plate and a plate adjacent thereto;wherein each channel extends from an outside edge of the at least onesecond plate to an interior of the at least one second plate in fluidcommunication with the aperture for guiding at least a portion of thejetting stream in a radial, curvilinear outward direction from andsubstantially parallel with a longitudinal plane of the at least onesecond plate; and wherein a sum of circumferential widths of theplurality of channels along an edge of the aperture is substantiallygreater than a sum of circumferential widths of the ridges along theedge of the aperture.
 2. The nozzle as claimed in claim 1, wherein saidfirst and at least one second plate are thin and cylindrical, andwherein the respective outer diameters of said first and at least onesecond plate and any intermediate similarly stacked plates,progressively decrease or increase.
 3. The nozzle as claimed in claim 1,wherein said pair of ridges comprises a plurality of ridges, and eachridge extends from an outside edge of the plates toward the center ofeach plate in a radial curvilinear manner for guiding at least a portionof the jetting stream from an interior of said nozzle outwardly in aradial, curvilinear outward direction and substantially parallel with alongitudinal plane of the plates.
 4. A nozzle for use within a filterfor inputting a jetting stream into filter media, the nozzle comprising:an inlet for communication with a jetting stream source; and a firstplate and at least one second plate having respective flat surfaces andstacked parallel to each other with said flat surfaces spaced apart fromeach other, the first plate having an aperture through the centerthereof for receiving the jetting stream, said respective flat surfacesof each of the first and at least one second plate being opposite toeach other and perpendicular to a stacking direction thereof; wherein atleast one of the first and at least one second plate includes at least apair of ridges on one of the opposite flat surfaces thereof which eachabuts a respective flat surface on one of said first and at least onesecond plates adjacent thereto defining a plurality of channels, eachpair of ridges defining a respective channel between them and betweensaid plate and the plate adjacent thereto; wherein each channel extendsfrom an outside edge of said plate to an interior of said plate in fluidcommunication with the aperture for guiding at least a portion of thejetting stream in a radial, curvilinear outward direction from andsubstantially parallel with a longitudinal plane of said plate; andwherein sum of circumferential widths of the plurality of channels alongan edge of the aperture is substantially greater than a sum ofcircumferential widths of the ridges along the edge of the aperture. 5.The nozzle as claimed in claim 4, wherein said first and at least onesecond plate are thin and cylindrical, and wherein respective outerdiameters of said first and at least one second plate, and anyintermediate similarly stacked plates, progressively decrease orincrease.
 6. The nozzle as claimed in claim 5, wherein said pair ofridges comprises a plurality of ridges, and each ridge extends from anoutside edge of the plates toward the center of each plate in a radialcurvilinear manner for guiding at least a portion of the jetting streamfrom an interior of said nozzle outwardly in a radial, curvilinearoutward direction and substantially parallel with a longitudinal planeof the plates.
 7. The nozzle as claimed in claim 1, wherein the outerdiameters of the first and second plates are substantially varied. 8.The nozzle as claimed in claim 1, wherein the nozzle comprises aplurality of second plates, each of the plurality of second platescomprising an aperture through the center thereof; and wherein theapertures of the second plates have successively reduced diameters. 9.The nozzle as claimed in claim 1, wherein the ridges are of uniformlength and a height of each channel is defined by a height of theridges; and wherein said height of the ridges is less than a minimumnominal diameter of media to be cleaned in the filter.
 10. The nozzle asclaimed in claim 9, wherein the height of the ridges is between 2 and 30mm.
 11. The nozzle as claimed in claim 4, wherein the ridges are ofuniform length and a height of each channel is defined by a height ofthe ridges; and wherein said height of the ridges is less than a minimumnominal diameter of media to be cleaned in the filter.
 12. The nozzle asclaimed in claim 11, wherein the height of the ridge is between 2 and 30mm.